Add workspace initial support

[aon]

Summary

Closes #1357

• [n] y/n | Does it introduce breaking changes?
• [n] y/n | Is it dependent on the specific version of ink or pallet-contracts?

Adds unstable flag workspace-mode that enables the usage of cargo-contracts inside a workspace package.

Description

Initially, this PR aimed to address use-ink/ink#1919, but it also fixes the issue when running cargo-contract.

This PR fixes the issue by changing in the manifest all workspace-inherited dependencies to normal dependencies. This is done by grabbing the workspace definition, and merging the dependencies with the ones defined in the crate.

For example if the workspace Cargo.toml is:

# Cargo.toml
[workspace]
members = ["contract"]

[workspace.dependencies]
ink = { version = "4.3.0", default-features = false }

And the contract Cargo.toml is:

# contract/Cargo.toml
[package]
name = "contract"
version = "0.1.0"
edition = "2021"
authors = ["[your_name] <[your_email]>"]

[lib]
path = "lib.rs"

[features]
default = ["std"]
std = [
    "ink/std",
    "scale/std",
    "scale-info/std",
]
ink-as-dependency = []

[dependencies]
ink = { workspace = true, default-features = true }

Then when building, cargo-contract will use a Cargo.toml with merged dependencies:

# contract/Cargo.toml
[package]
name = "contract"
version = "0.1.0"
edition = "2021"
authors = ["[your_name] <[your_email]>"]

[lib]
path = "lib.rs"

[features]
default = ["std"]
std = [
    "ink/std",
    "scale/std",
    "scale-info/std",
]
ink-as-dependency = []

[dependencies]
ink = { version = "4.3.0", default-features = true }

Checklist before requesting a review

• My code follows the style guidelines of this project
• I have added an entry to CHANGELOG.md
• I have commented my code, particularly in hard-to-understand areas
• I have added tests that prove my fix is effective or that my feature works
• Any dependent changes have been merged and published in downstream modules

[cla-bot-2021]

User @aon, please sign the CLA here.

[SkymanOne]

We need to understand what repercussions it has on a crate publishing process. We've experienced some issues with the release process in ink! where come internal crates had cyclic dependencies

[ascjones]

We need to understand what repercussions it has on a crate publishing process. We've experienced some issues with the release process in ink! where come internal crates had cyclic dependencies

This PR is to do with user contract projects with workspace dependencies.

That said, this project itself could also be upgraded to use workspace dependencies, I think hernando started a PR for that somewhere.

[aon]

I agree this should be the default behaviour, just wanted to add it for now as unstable given it's not proven yet how well it works.

I'm unsure on the part about cyclic dependencies and how could this small change affect the crate publishing process?

On another note, I believe the CI is failing but due to unrelated things.

[ascjones]

I agree this should be the default behaviour, just wanted to add it for now as unstable given it's not proven yet how well it works.

I'm fine with bringing it straight in, if it is well tested. i.e. works to compile all existing ink-examples, and with a workspace example. Maybe we should add an example workspace crate layout as part of this PR to test that it works.

I'm unsure on the part about cyclic dependencies and how could this small change affect the crate publishing process?

I believe @SkymanOne was referring to the issues we experienced when migrating ink itself to workspace dependencies. I don't think this is an issue for this PR since we are dealing with the target contract crate workspace.

On another note, I believe the CI is failing but due to unrelated things.

Should be fixed once #1352 is merged. Just merge in master.

[aon]

@ascjones I have created a PR in ink-examples following your recommendation, showing how it works. use-ink/ink-examples#44

[cla-bot-2021]

User @faculerena, please sign the CLA here.

[faculerena]

Pull request comments addressed.

[ascjones]

LGTM thanks!

[valeriacaracciolo]

@ascjones I have created a PR in ink-examples following your recommendation, showing how it works. paritytech/ink-examples#44

We (@faculerena, @tenuki) closed this PR due to some problems with checks and opened PR paritytech/ink-examples#52 as a replacement.